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arXiv · 0904.1019

Relativistic Mott criticality in graphene

Igor F. Herbut·Vladimir Juricic·Oskar Vafek
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Abstract

We formulate the effective Gross-Neveu-Yukawa theory of the semimetal-insulator transitions on the honeycomb lattice and compute its quantum critical behavior near three (spatial) dimensions. We find that at the critical point Dirac fermions do not survive as coherent excitations and that the $\sim 1/r$ tail of the weak Coulomb interaction is an irrelevant coupling. The emergent Lorentz invariance near criticality implies a universal ratio of the low-temperature specific heats of the metallic and the rotational-symmetry-broken insulating phase.

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Igor F. Herbut, Vladimir Juricic, Oskar Vafek. 2009-09-22. Relativistic Mott criticality in graphene. https://doi.org/10.1103/physrevb.80.075432

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